Air and gas compressor.



H. L.BORCHERS. AIR AND GAshoMPRBsson.

APPLICA TION FILED NOV. 4, 1907.

Patented Dec. 1, 1908.

INVENTORI lllxlllll l 'UNITED 'STATES PATENT OFFICE.

HERBERT L. BORCHERS, OF DENVER, COLORADO.

AIR AND GAS COMPRESSOR.

Specification of Letters Patent.

Patented Dec. 1, 1`9o8.

IApplication sie@ November 4, 1907. serial No. 400,433.

`tion ofa twostage, double acting compressor which shall be simple in construction and efiicient inl operation.` The accompanying drawing isa longitudinal sectional view of the compressor.

, In said drawing, the low pressure cylinder 1 is connected to a suction chamber 2 comprising a. dome-.shaped casting which is bolted to said cylinder; Between the flanges at the ends yof'said cylinder and suction chamber is secured a plate 4 forminga seat for thespring pressed valve-5, whichjaffords a means of communication between said cylinder and suction chamber. The valve 5 is provided with a stem 6 which slides through the guide 8 supported by arms 9 which are connected with the plate 4. Said valve stem 6 forms a guide and support for the coiled spring 10, held in position by the nut 11, which may be turned to regulate the tension of said spring. The suction chamber is supplied with air or gas through the supply pipe 12.

Within the cylinder 1 is what may be termed a piston-cylinder 15, having an enlarged end 16 pr` vided with grooves 17 for the reception 0'? the packing 18. This end of the piston-cylinder is provided with two spring` pressed valves 19 and 2O secured to a common stem 21 passing through the guide 22 supported from the interior of said piston cylinder. These valves are of smaller area than the suction Valve 5. The provision of the two valves 19, and 20, is necessary to obtain the required small clearance space between valve 5, and piston head 16; and between the valve 20, and piston head B2, on the completion of the forward and backward strokes respectively. The space between said valves is necessary to receive their operating mechanism. The chamber 41 included within the cylinder 1 and between the valves 5 and 19 is the low pressure cha o.- ber. The right hand end of said piston cylinder is connected to the cross-head 2t' by means ofthe rods 26 and 27, passing through holes 28 and 29 respectively in the cylinder head 30. Said cylinder head 30 is bolted to the right hand end of the low pressure cylinder 1, and has formed therewith a hollow H chamber 31 provided with an enlarged end 32 which acts as a stationary piston for the piston-cylinder 15. This enlarged end is packed to provide a tight joint between it and said piston-cylinder, and is also prog;

vided with a. seat 33 for the spring pressed valve 34. Said valve is provided with a stem 35 passing through a guide 36 and surrounded by a spring 37. The guide 36 is connected to a screwthreaded support 38 which may be moved to vary the tension of the spring-37.I The chamber 42 within the pis- `ton-cylinder'l and between thevalves 20 and- 34 is fthefhigh pressure chamber. To* the.

ou-terface-of t e cylinder head 30 is bolted 'thefdisc'harge outlet 39 which comprisesa plate 40 which forms a head for the cylinder 31. The area of the valve 34 is smaller than that of the valves 19 and 20.

The operation of the device is as follows: When the piston cylinder is moved forward, that is, toward the crosshead 25,'by means of its connection with said crosshead, the suction valve 5 opens and admits air or gas to the low pressure chamber 41. `Vhen the piston cylinder 15 returns the valve 5 closes and the gas in the low pressure chamber 41 is compressed sufficiently to open the double valves 19 and 20, and be forced through them into the high pressure chamber 42. When said piston-cylinder 15 againmoves toward the crosshead 25, a new charge of gas is drawn into the low pressure chamber 41, and the gas in the high pressure chamber 42 is ycompressed sufficiently to open the valve 34 and pass into the discharge chamber 31, from which it is discharged through the outlet 39.

From the above description it will be seen that the gas undergoes two stages of compression and the device is double acting. By carrying the stationary piston 32 forward into the piston cylinder 15 the high pressure chamber 42 is formed, yet allowing the minimum length of cylinder 1 to be employed. By forming the high pressure chamber within the piston-cylinder its internal "diameter is reduced, thus tending to equalize the pressures upon opposite sides of the piston.

Cri

Having thus described my invention, I claim i. a compressor, the combination of a low pressure cylinder; a chamber projecting inwardly from one end thereof and havin an axial puppet valve in its inner end; a :no1/able cylinder within said low pressure cylinder having one end formed into a hol loir piston; and ay pair of axial valves connected to operate simultaneously and each seated in an end Wall of said hollow piston.

2. in a compres `lor, the combination of a low preszure cylinder; a piston cylinder wlioliy within said 10W pressure cylinder, having an enlarged end which forms one end or" a low pressure chamber Within said 10W pressure cylinder; a hollow stationary piston secured to one end of said low pressure cylinder and extending Within said piston cylinder to form therewith a high pressure chamber; means for moving said piston cylinder; and means for controlling the flow of gas between said chambers.

In a compressor, the combination of a lov.7 pressure cylinder; a piston cylinder Within said low pressure cylinder having an enlarged end which forms one endofa 10W pressure chamber; a stationary piston secured to one end of said loviT pressure cylinder and extending Within said piston cylinder to form therewith a high pressure chamber; a pair of valves in the end of said piston cylinder for affording communication between thel low and high pressure chambers; a valve in said stationary piston;

and means for' supplying gas to said low pressure chamber.

4.-. In a compressor, the combination of-.an outer cylinder; a chamber rejecting 1n- Wardly from one end of saidJ cylinder; an axial valve in one end of said chamber; an axial valve in one end of said outer cylinder; a piston cylinder Within said outer cylinder and co-acting with the inner end of said chamber; and a valve in the end of said piston cylinder.

5. In a compressor, the combination of an outer cylinder; a chamber projectingin- Wardly from one end of said cylinder; an axial valve in one end of said chamber; an axial valve in one end of said outer cylinv der; a piston cylinder Within said outer cylinder and co-actng with the inner end of said chamber; and a pair of axial valves in the end of said piston cylinder.

6. In a compressor, the combination of an outer cylinder; a chamber rojecting in- Wardly from one end of said) cylinder; an axial valve in one end of said chamber; an axial valve in one end of said outer cylinder; and a piston cylinder Within said outer. cylinder provided with a chamber having a air of axial valves in its Walls.

In testimony whereof, I have hereunto signed my name, at Denver, Colo., this 29th day of October 1907.

l HERBERT L. BORCHERS.

Witnesses:

ARTHUR COOPER, EDwiN ARTHUR COOPER. 

